NASA's future exploration missions focus on the manned exploration of the Moon, Mars and beyond, which will rely heavily on the development of a reliable communications infrastructure from planetary surface-to-surface, surface-to-orbit and back to Earth. Flexible antennas are highly desired in many scenarios, such as pressurized rovers, pressurized habitats, space suits, and any other applications that require conformal profiles. Existing flexible electronics has an intrinsic low switching frequency due to their low carrier mobility. The CNT network in solution we used has carrier mobility as high as 46770cm2/V's and a large current-density carrying capacity of ~1000 mA/cm2, corresponding to a high carrying power of over 2000mW/cm2. Such high carrier mobility and large current carrying capacity allow us to achieve high-speed (>100GHz), high power flexible electronic circuits and antennas. A prototype of a fully printed S-band 4-bit 2D (4x4) 16-element PAA on flexible substrate such as Kapton, including FET based T/R module and phase shifters will be developed and optimized. For the FETs working as switches/amplifiers, the switch speed, on-off ration, the gain, noise figure, insertion loss and power consumption will be significantly improved through finding better gate dielectric material, increasing the CNT purity and the optimizing the FET geometry including the channel length and the channel width. Performance features of the printed PAA will be characterized including frequency/bandwidth, gain/efficiency, and power consumption. To survive NASA's stressing environment, the operating temperature range will be investigated and the performance under shock and vibration will be evaluated. The humidity test and aging tests will also be carried out. Radiation hard test will also be carried out in Phase II under the program manager's guidance.